Detachable meter construction



Dec. 29, 1936. G, MYU US 2,060,300

DETACHABLE METER CONSTRUCTION Original Filed Jan. 19, 1935 WITNESSES:

INVENTOR Y, W BY %/AE?I% 2/ Patented Dec. 29, 1936 2,066,300 DETAOHABLEMETER CONS'I'BUGHON Walter G. Mylius, Summit, N. 1., a-ignor to acturlngWestinghouse Electric a Mann! Company. East Pittsburgh, Pa., -acorporation Pennsylvania Original application January is, loss, SerialNo.

2.534; Divided application March 12, 1936, Serial No.68,889

1 Claim. .(Cl. 113-324) The present invention relates to watthour metersof the general character shown in United States Patent No. 1,969,499,issued August 7, 1984, and more specifically to an improved constructionof the terminal chamber or sub-base upon which such meters aresupported.

This application is a division of Serial No. 2,534 filed January 19,1935 by Walter G. Mylius, assignor to Westinghouse Electric &Manufacturing in pany.

In meters of the above mentioned character, usually called thedetachable type, four contact blades usually project from the basethereof and are connected inside the meter to the current and 15potential windings. Two of the blades are for connection to the incomingor supply circuit, and the remaining two are for connection to the loadcircuit. The terminal chamber or sub-base for such a meter usuallycomprises, as in the above go numbered patent, four contact jaws, two ofwhich are for connection to the supply circuit and the other two to theload circuit, and which are adapted to receive the contact bladesprojecting from the meter base. I

as The terminal chamber or sub-base is usually provided withdiametrically opposite openings in its side walls for receiving theconduits housing the supply and load leads of the circuit to beinserted. Buch conduits may extend vertically, in

so which event the openings will be in vertical alignment, or theconduits may extend horizontally, necessitating a 90 rotation of theterminal chamber, with an attendant rotation of the jaw alignment.

35 These alternate possibilities would normally render it necessary tomanufacture and stock two lines of chamber, that is, for vertical andhorizontal conduit systems, so that the meters may always be installedin a proper upright position,

40 and it is an object of the present invention to avoid this expensiveand complicated practice in a simple and satisfactory manner.

Other objects will be apparent from the following description andaccompanying drawing 45 wherein:

Figure 1 is a plan view of a terminal chamber or sub-base for a meter ofthe detachable type embodying the present invention, and showing thecontact jaw arrangement for mounting with 50 a vertically extendingconduit system.

Fig. 2 is a view of a portion of the structure shown in Fig. 1 adaptedfor horizontal conduit systems:

Fig. 3 is an enlarged view in section, taken on 55 theline m-m of Fig.l; and

Fig. 4 is a view in section, parts being broken away, of a terminal usedin conjunction with the invention.

Referring more specifically to the drawing, the terminal chamber orsub-base com'prises'a sub- 5 stantially cylindrical chamber 2 havingdiametrically-opposed threaded bosses l for receiving suitableconduitiittings. It is contemplated that the supply conductors willenter through one of the threaded bosses t and be connected with thesupply terminals within the chamber, as hereinaiter described, and theload conductors connected to other terminals will leave the chamberthrough the other threaded boss 4.

The chamber 2 may be secured to a support inany suitable manner, as byinserting screws through apertures t, or by making use of the centrallydisposed screw 1 which may also be used for making a ground connection,11 such is required.

Within the chamber 1 are disposed two terminal blocks '8, suitablysecured to the base of the chamber, as by screws II, and disposed onopposite sides of the threaded bosses I to define substantially achannel communicating with such 5 bosses for receiving the circuitconductors.

Each terminal block 0 has secured thereon two contact jaws I! each ofwhich is electrically connected to a conducting strap It securedto astrap II by means of a screw it. The strap It is electrically connectedwith a terminal post It. adapted to be connected to one of the wires ofthe circuit with which the meter is to be associated.

It is contemplated, in usual practice, that two service conductors willenter through the upper boss 4 and be respectively connected to theupper terminal posts Il,- and two load conductors will extend throughthe lower boss 4 and be electrically connected to the lower terminalposts 20. 40

Each contact jaw It comprises a member of substantially U-shape,preferably of resilient strip material, having the free ends thereofreturn-bent to define a slot for receiving a contact blade projectingfrom the base of a detachable meter. As shown in Fig. 3, the jaw I2 ismaintained in position by means of a screw 22, extending upwardlythrough the block 8 and the base of the jaw, into threaded engagementwith the one end of the conducting strap It.

The confronting surfaces of the jaw I! are spaced a distance less thanthe thickness of a contact blade of the meter, and the extremities oisuch surfaces may be in contacting relation, or

substantially so, so that the entering contact blade tightly grips theblade to insure an emcient electrical contact.

The terminal posts 20, as shown more clearly in Fig. 4, are of a usualconstruction comprising a threaded bushing secured, at the base thereof,to the block 8 by means of a bolt 2| extending downwardly from the basethrough the block 8 for engagement with a suitable securing nut, andhaving a screw 24 entering the upper end to clamp against a. conductorinserted through a laterally extending aperture 26. A portion of thebolt 2i extending through the strap I6 is squared and the opening instrap I6 is similarly shaped to prevent rotating of the terminal postwith reference to the strap.

The consumers load may be disconnected, when desired, by breaking theelectrical connection between the conducting straps l4 and I 6, of anyor all of the jaws i2 and terminals 20. This construction is shown indetail in Fig. 3 with reference to one of the jaws. It will be noted,referring to Fig. 3, that the strap l6 upon which the terminal post 20is supported normally lies slightly below the plane of the lower face ofthe strap H, a depression being formed in block 8 for this purpose. Thescrew l8 extends loosely through the strap l4 into threaded engagementwith an aperture in strap l6. Loosening of screw I8 permits strap 16 todrop out of engagement with strap l4 thereby breaking the circuit fromthe jaw l2 to the terminal post 20. If, therefore, it is desired todisconnect a consumer's circuit, the meter may be removed and screws l8,or any of them, may be loosened and the meter reinserted in position andproperly sealed to prevent reconnection of the consumers circuit.

In the event that the conduit system, with which the chamber 2 is to beused, extends in a horizontal direction, necessitating a rotation of thecasing 2, through an angle of 90 from the position shown, it isnecessary to alter the positions of the jaws l2, so that the watthourmeter may be installed in its proper upright position.

In order to take care of this condition, each jaw has associated with itanother aperture in the block 8 equidistant from the center lines of theapertures occupied by screws 22 and of terminals 20; that is, thecenters of aperture 30, law

l2, terminal 20 and screw l8 define a square. After loosening thevarious screws, the straps H and li'may be rotated toward each other,about the screw 22 and terminal 20 as axes, respectively, to theposition shown in Fig. 2 with the screw l8 in the auxiliary aperture 30.This results in the jaw I2 also being rotated 90 to be in position toreceive the blade contact of the meter.

It should also be apparent that the construction shown and described isapplicable to purposes other than mounting watthour meters, and may beused for mounting indicating instruments. time-switches, or in fact anyelectrical instrumentality which may be adapted to this type ofmounting,

The apertures for the screws 22 of the four contact blades also define asquare, so that when the chamber 2 is rotated 90 from the position shownin Fig. 1, and the straps ll and it of each jaw rotated as described inthe preceding paragraph, the apparatus is prepared for association witha horizontally extended conduit system with the four jaws properlydisposed to receive the contact blades of a meter.

Quite obviously various modifications may be made in the inventionwithout departing from the spirit and scope thereof, and it is desiredthat only such limitations shall be placed thereon as are imposed by theprior art and set forth in the appended claim.

I claim as my invention:

In a terminal block, four equally spaced apertures definingsubstantially a square, a terminal post and means extending through oneaperture for securing it to said block, a contact jaw and meansextending through a diagonally opposite aperture for securing it to saidblock, electrical conductors extending from said post and jaw and havingregistering openings in the free ends thereof registering with anotherof said apertures, the construction being such that the jaw and postwith their conductors may be rotated 90 toward each other so that theregistering openings in the free ends of the conductors will registerwith the remaining aperture in said block.

WALTER G. MYLIUS-

